Modeling and simulation of vehicle integrated thermal management system for a fuel cell hybrid vehicle

The high-efficiency thermal management is one of the major challenges for fuel cell vehicles due to the diversity and complexity of the components and systems. Thermal management systems and corresponding control strategies can affect the components' performance, durability and reliability, the vehicle's driving performance, fuel economy and occupant thermal comfort. The main objective of this study is to perform multi-case simulation analysis of the fuel cell vehicle thermal management system through modeling to derive the operating mechanism and thermal performance analysis of each subsystem and integrated system. To achieve this purpose, an integrated thermal management system model with different control strategies was proposed based on a fuel cell vehicle prototype, powered by a 65 kW proton exchange membrane fuel cell stack and a Li-ion battery with a capacity of 15 kWh, which considers the cooling of the driving system, fuel cell stack, battery and cabin. The results showed that the critical temperature of each subsystem could be controlled within a reasonable range even in the battery charging mode, where the fuel cell generated about 136.6 % more thermal power than the discharging mode to charge the battery. Moreover, in the series structure of the radiators and condenser, the average temperatures of the inlet air of the motor and the subsequent fuel cell radiator were respectively 3.9 degrees C and 7 degrees C higher than the ambient temperature (35 degrees C), thus reducing the impact of the radiator fan. The proposed model may provide the contribution in the design of integrated solutions for thermal management systems for fuel cell hybrid vehicles under high temperature scenarios, including control strategies development and systemlevel coupling analysis.